Study 15 terms lab report 9 pure culture technique. Sterilization, culture media and pure culture techniques. Their importance to biotechnology and microbiology khursheed a. Microbiology is a popular option for practical work in schools. Microbial cultures are foundational and basic diagnostic methods used extensively as a research tool in molecular biology. June 2002 overview this microbiology laboratory manual is designed especially for the nonmajors, health science. Pdf microbiology exercise 6 and 7 pure culture technique. Essential methods for maintaining, preparing and using cultures. In streak plate culture method, a sterilized loop or transfer needle is dipped into the mixed culture of the specimen.
A pure bacterial culture remains essential for the study of its virulence, its antibiotic susceptibility, and its genome sequence in. Their small size means you cant go to a zoo or take a safari to study these creatures. Learn pure cultures microbiology with free interactive flashcards. Microbiologists use aseptic technique for a variety of procedures such as transferring cultures, inoculating media, isolation of pure cultures, and for performing microbiological tests. This manual has been written for a righthanded person. A pure culture is usually derived from a mixed culture one containing. Aseptic technique in laboratory preparation and analysis. Beijerinck made two major contributions to microbiology. To isolate pure cultures from a mixture of bacterial species.
These techniques include the transfer of microbial cells from one medium to. In this chapter, we examine in some detail these techniques. It is important to label the vial with all the relevant. Basic practical microbiology why microbiology matters. Current and past strategies for bacterial culture in clinical. Different types of culture media used in microbiology pdf. The society aims to encourage a greater public understanding of microbiology and biotechnology by. In pour plate technique, successive dilutions of the inoculum serially diluting the original specimen of old broth culture is added to the sterile petri plates containing the melted and. Pure culture may be compared to a bed of roses obtained in pure culture of roses. A pure culture can become contaminated by other bacteria from sources such as the air, skin or. Microbiology encompasses numerous subdisciplines including virology, bacteriology, protistology, mycology, immunology and parasitology. Learn vocabulary, terms, and more with flashcards, games, and other study tools. A pure culture may be isolated by the use of special media with specific chemical or physical agents that allow the enrichment or selection of one.
This is a useful technique for pure culture of fungi, multicellular algae, and small metazoa. While his work on the tobacco mosaic virus established the basic principles of virology, it was his development of enrichment culturing that had the most immediate impact on microbiology by allowing for the. The modern pour plate culture method was initially developed in the laboratory of the famous bacteriologist and the father of bacteriology, dr. Microbiologists and health workers use this technique to prevent. Objectives to demonstrate good aseptic technique in culture transfer or inoculation and in handling sterile materials. Laboratory sessions are focused on pure culture techniques, methods of staining and the microscopic, colonial and biochemical identification of microorganisms. The first isolation of a bacterium enables the design of experimental models to analyze virulence and to complete kochs criteria, thereby establishing a link between microorganisms and infectious diseases. Start studying lab report 9 pure culture technique. The single colony is transferred picked to a fresh medium to obtain a larger, homogeneous culture that may be studied and characterized by a variety of techniques. Perform a pourplate loop dilution to separate cells of a mixed culture and compare growth characteristics beneath and on the surface of the agar. Differences in the genome sequences of kn400 and dl1 were too great to have arisen from adaptive.
Microbiology lab 4 sept 25 pure culture techniques. Laboratory manual and workbook in microbiology applications to patient care 7th edition josephine a. Microbiological laboratory techniques clinical gate. Pdf microbiology biol 275 pure culture techniques dendra. In addition, almost all microbiologists use a wide variety of other techniques, especially. Sep 09, 2014 this general microbiology practical lecture explains the pure culture isolation techniques like streak plate, spread plate and pour plate method. Pure culture, in microbiology, a laboratory culture containing a single species of organism. Sep 25, 2019 pure cultures of multicellular organisms are often more easily isolated by simply picking out a single individual to initiate a culture. Pure culture technique food samples and other materials commonly contain mixed populations of different microorganisms.
Specimen collection and transportation of microbiology. To demonstrate skill in isolation of organisms from a mixed culture using selective and differential media. Pure culture isolation of candidatus arsenophonus arthropodicus. Simpler methods for isolation of a pure culture include. As proposed by robert koch, a pure culture is the foundation of all research in infectious diseases 1, 2. Isolation of pure cultures a pure culture theoretically contains a single bacterial species. The preparation of a pure culture aims at the isolation of a given microorganism from a mixed population. Sep 09, 2014 this general microbiology practical lecture explains different bacterial culture techniques like spread plate and pour plate method. This general microbiology practical lecture explains different bacterial culture techniques like spread plate and pour plate method. Most specimens from animal tissue, plant tissue, or environmental samples will be mixed, with a variety of bacteria o r other microorganisms. Proper aseptic technique prevents contamination of cultures from. D3400 gottingen, federal republic of germany introduction.
The inoculum is streaked over the agar surface in such a way that it thins out the bacteria. The streak plate culture technique for the isolation of microorganism is the most practical method of obtaining discrete and welldeveloped colonies of the microbe in pure cultures. If you need to print pages from this book, we recommend downloading it as a pdf. These methods constitute a core of techniques common to all microbiology. A pure culture is usually derived from a mixed culture one containing many species by transferring a small sample into new, sterile growth medium. The differential and selective procedures will be utilized later in this course. A pure culture is usually derived from a mixed culture one containing many species by transferring a small sample into new, sterile. The commonly used standard method is nutrient agar culture, where after centrifugation and subsequent spreading of the sample on the nutrient agar, subculturing is done to obtain the pure colony.
A pure culture may be isolated by the use of special media with. Streak plate technique is used for the isolation into a pure culture of the organisms mostly bacteria, from a mixed population. Isolation of bacteria in pure culture microbiology. Isolation of pure culture is vital for characterizing a single species of bacteria otherwise presence of contaminants can lead to inaccurate observations. This method is used most commonly to isolate pure cultures of bacteria. Isolation and observation of bacteria using pure culture. This manual, which explains the basic techniques necessary to carry out microbiology experiments safely and effectively, is intended as a guide for teachers and technicians.
A pure culture is usually derived from a mixed culture one containing many species by transferring a small sample into new, sterile growth medium in such a manner as to disperse the individual cells across the medium surface or by thinning. Take the overnight culture and and mix an aliquot with 40% glycerol in sterile water and place in a cryogenic vial. The methods, used to isolate the bacteria in pure culture, consist of separating a single living bacterial cell and allowing it to multiply on a suitable culture medium, usually in a solid medium, to form a pure. Microbiology exercise 6 and 7 pure culture technique and aseptic transfer of microorganisms and cultural characterization of bacteria. Isolation, pure culture, and characterization of candidatus. The pure culture is derived from the mixed culture by transferring a small sample into a new sterile growth medium in a manner that disperses the individual cells across the mediums surface. This process is called inoculation and the growth that appears on or in the medium is the culture. A gram stain also helps to identify mixtures of bacteria, helps to determine the appropriate range of agar plates to be used for subsequent culture, and helps with the interpretation of culture results. Start studying microbiology lab 4 sept 25 pure culture techniques. There are a number of procedures available for the isolation of pure cultures from mixed populations. Current and past strategies for bacterial culture in. Microbial cultures are used to determine the type of organism, its abundance in the sample being tested, or both. Pure culture techniques, such as streak plate, pour plate and spread plate, isolate bacterial colonies from mixtures so that colonies comprising of the identical organisms can be studied.
Pure culture techniques university of pennsylvania. Practicing aseptic technique with microbial cultures flinn scientific. Finally, pure bacterial culture enables manipulation and transformation by adding or deleting genes to analyze the cause of virulence and antibiotic resistance and the invasive potential of bacteria. Basic laboratory techniques in microbiology must be mastered not only by the microbiologists, but also by molecular biologists, geneticists, biochemists and many other scientists, as these techniques are used as tools in many disciplines. The microbiology society, in association with the microbiology in schools advisory committee misac. Unfortunately, this book cant be printed from the openbook.
In the study of microbiology, there are numerous occasions when it is. In order to ensure a pure culture is being preserved, pick a single colony of the bacteria off a plate, grow it overnight in the appropriate liquid media, and with shaking. The methods, used to isolate the bacteria in pure culture, consist of separating a single living bacterial cell and allowing it to multiply on a suitable culture medium, usually in a solid medium, to form a pure colony. Methods of culturing microorganisms 3 five basic techniques 4 fig. Module context this module introduces microbiological laboratory techniques to be used for analysis of coliforms bacteria can be used as indicators of pollution.
Aseptic technique and the transfer of microorganisms. Act of cultivating microorganisms or the microorganisms that are cultivated mixed culture. It can also be derived by thinning the sample manifold before inoculating the new medium. If a specimen is to be collected through intact skin, cleanse the skin first. For pure culture isolation, we used methods described previously for the solidphase culture of s. The following points highlight the top six methods used for obtaining pure culture of microorganisms. Subculturing is one of the microbiological techniques that lets you raise them properly by transferring some microbes from one environment to another. Microbial culture methods boundless microbiology lumen learning. Maintenance and preservation of pure cultures of bacteria.
Quickly pass mouth of vial several times through burner flame. If you continue browsing the site, you agree to the use of cookies on this website. Lectures are focused on the structure of prokaryotic and eukaryotic microorganisms, hostmicrobe interactions, immunity and human infectious diseases. For the purpose of gelling the microbial culture, the medium of agarose gel agar is used. Aseptic technique is a fundamental and important laboratory skill in the field of microbiology. Subculturing is a microbiological technique that lets you raise them properly by transferring some. A pure or axenic culture is a population of cells or multicellular organisms growing in the absence of other species or types. Perform a streakplate to separate the cells of a mixed culture so that discrete colonies can be isolated. Microbiology module methods of isolation of bacteria microbiology 112 notes properties gram positive. A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture media under controlled laboratory conditions. The society for general microbiology sgm is a learned society with over 5,000 members worldwide who work in universities, industry and research institutes. The most commonly used instrument in the microbiology laboratory for the sterilization of media and. A pure culture may originate from a single cell or single organism, in which case the cells are genetic clones of one another. Sep 25, 2019 a pure or axenic culture is a population of cells or multicellular organisms growing in the absence of other species or types.
Perform a pourplate loop dilution to separate cells of a mixed culture and. Ayush vikram singh sl1444 ujjwal singh sl144414 gft 2. Sep 11, 2011 micro students may find this presentation on culture methods useful slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Microbiology is the study of organisms too small to see with the naked eye. This general microbiology practical lecture explains the pure culture isolation techniques like streak plate, spread plate and pour plate method. Choose from 500 different sets of pure cultures microbiology flashcards on quizlet. Introduced solid media for culture of bacteria and use of agar methods of isolation of bacteria in pure culture described hanging drop method for motility of organism. Remove vial cap using little finger of same hand that holds inoculating loop. Geobacter sulfurreducens strain kn400 was recovered in previous studies in which a culture of the dl1 strain of g.